In conventional electrical contact devices in which a tubular electrical element fits onto a jack-like electically conductive contact extension of electrical device body secured to a wire, the inner surface of the element directly contacts the outer surface of the extension of the device. This electrical contact typically is not satisfactory because of surface irregularities in the mating surfaces of the element and the extension. This causes a limitation in the amount of current that can be carried across the junction of the mating surfaces because of the relatively high contact resistance. Because of such resistance, the voltage drop is relatively high and a relatively high increase in temperature of the mating surfaces occurs due to the high contact resistance.
The foregoing drawbacks are significant in that they represent circuit losses which are not acceptable. As a result, more expensive equipment is needed to avoid such losses, thereby increasing circuit costs considerably. Because of these drawbacks, a need exists for improvements in electrical contact units in which two parts are releasably interconnected. The present invention satisfies this need.